Researchers find way to control growth rate of replacement blood vessels, tissues

Washington, Mar 7 : Researchers at the University of Michigan School of Dentistry and College of Engineering have found a way to control the growth rate of replacement tissue and the formation of new blood vessels.

The finding solves one of the vexing problems of growing replacement tissue to treat injuries and trauma in humans.

According to William Giannobile, professor at the University of Michigan School of Dentistry and College of Engineering, and co-author of the study, the procedure could be used in bone grafts, tissue replacement, and dental procedures or for diabetics or elderly patients who experience wound healing problems. "If you have such a large defect that your body can't completely heal, this is a way to augment and dose a natural wound healing protein," Giannobile said.

Giannobile and colleagues put platelet-derived growth factor into nanoparticles and then attached them to a lattice-like, biodegradable scaffold.

Peter Ma, co-author of the study said, in experiments, the growth factor recruited cells that stimulate the body's own machinery responsible for healing.

As the tissue grows, it crawls into the scaffold, which ultimately dissolves.

"Growth factor is typically dumped in and releases over a period of hours," Giannobile said.

"With certain wounds you might want a lot (of growth factor) in the beginning, and with others you might want a little released over a longer period of time. We've basically found a way to dial up or dial down the release rate of these growth factors," he added.

Platelet derived growth factor is FDA-approved for treatment of diabetic ulcers and to promote bone repair in tooth-associated defects, but time-release delivery has been a big problem.

Ma said that the one of the keys was finding a way to preserve the biological properties of the growth factor in the nanoparticle for controlled release.

Giannobile said that the next step is to evaluate a broader range of wounds, followed by early stage human studies.

The study is available online at the Public Library of Science.

ANI